"ITHACA, N.Y. – In order to deliver medicine inside the human body, nanoscale medical devices need energy to carry out tasks, such as releasing drugs. Alex Travis, Cornell assistant professor of veterinary medicine, suggests creating a system that generates power for nanoscale robots, based upon how sperm make energy to swim.

Travis will present his research at the American Society for Cell Biology Annual Meeting, Dec. 3, and he will discuss this idea at a press briefing in Room 101 of the Washington Convention Center at 10 a.m.

“One of the major limitations in making implantable, nanomedical devices is providing power to them,” said Travis, who conducts his research at the James A. Baker Institute for Animal Health, part of Cornell’s College of Veterinary Medicine. “If you can engineer a device that can make its own energy, then it can potentially last longer and regulate its own task rate.”

Another potential use for this technology: creating nanoscale pumps that could release chemotherapeutics or antibiotics into specific places in the body."

Is it even possible to provide your own constant energy? The only way around it would be to have the nano-tech use the kinetic energy of the subject - that seems like the only viable source. Then again... science was never my thing.

Somebody has made a machine that converts blood-sugar to electrical energy. It's not nanosized though... yet. Or you could convert it straight to sperm-energy if you used the right proteins and enzymes (hard).

I wouldn't bat an eyelid if they said that the Nano-bots were going to swim in the same fashion as sperm because their form of movement is energy-efficient, but yeah, what they're saying just begs the question: 'How do sperm generate energy?'

I know sperm aren't supposed to live for long after 'evacuating' the body, so I would have just assumed that they contained a small amount of energy in them, and when that was used up, that was it.

I can't see how movement through the body would a problem for nanomachines, though. Would they not simply be able to ride the blood stream if they were trying to get to, say, the brain or liver? Correct me if I'm wrong, but blood moves in an essentially circular fashion, thus moving oxygen and energy producing protiens about, right?

I would think the larger problem would be to have them stop once they are at the desired location, and begin the work they were implanted to begin with. How would one go about signaling that? Tiny transmitters? An implanted RF tag, constantly emitting "Here I am! I'm the liver! Come fix me!"?

Well, when you get down to the nanoscale, the blood is incredibly thick and difficult to get around in. As far as anything that small is concerned, it’s like being trapped in a thick jelly, so they need loads of energy to manoeuvre around and steer themselves. Being pumped about in the blood is fine if you want to go to the feet or the lungs, not so good if you want to go anywhere else.

To answer an earlier question, sperm are filled with mitochondria – the power pack of the cell- which gives them loads of energy. It would appear to me to be easier just to scoop out the DNA of the sperm and use that as your starting material rather than try and spend all the time building a tiny robotic version of it from scratch.

Thank you for the info. That makes a lot more sense than my supposition did. Out of curiosity (I'm asking you since you seem to be rather well informed), would the vein structure be porous enough to allow any type of nanotech to slip in and out at will? From my macro perspective, I tend to think of my veins as being solid, if liable to puncture, and had never thought to wonder before.

The cells lining blood vessels are usually pretty tightly bound together, because there are all sorts of proteins that you don’t normally want escaping from the vessel and acting on the cells underneath. They'd have to be smaller than the proteins to get out. When you get a wound, or in conditions such as cancer, the smaller blood vessels become quite ‘leaky’ to allow immune cells to get out of the blood and get to the site of injury or disease and do their immune cell thing. Also, it’s worth remembering that the bigger, major blood vessels are pretty thick and if anything wants to get out they’ll have to get through a load of cell layers to get out, which might not do the vessel much good. Smaller blood vessels are much thinner though.